Gelatin compositions containing a bisisomaleimide hardener



United States Patent C) M 3 232 763 GELATIN coMPosmoNs CONTAINING A BISISOMALEIMIDE HARDENER Donald M. Burness and Burton D. Wilson, Rochester,

3,232,763 Patented Feb. 1, 1966 Example 1 The procedure described by Cotter, Sauers and Whelan, Journal of Organic Chemistry, volume 26, page 10 (1961), was followed using commercial dicyclohexyl- N.Y. assignors to Eastman Kodak Compan Roches- 5 carbodiimide. The product obtained was in the form of 9 ter, N.Y., a corporation of New Jersey colorless crystals in 52% yield which product had a meltl\o Drawing. Filed Mar- 14, 1 ing point of 96.597.5 C. Samples of this product, Claims? hexamethylene bisisomaleimide, were added to separate portions of a high speed gelatin-silver bromoiodide emul- Thls lnvemlon relates to gelatm coatmg compqsltlons 10 sion, which had been panchromatical-ly sensitized with a d layers prepared therefrom composed of ge af and cyanine dye, in the proportions indicated inthe table. as a hardener therein an alkylene 'bislsomaleirmde, the AS a comparison Samples of the emulsion Without illkylelflfi e 0f 10carb0n atoms" hardener added and with hexamethylene bismaleimide in VaTlOllS blsmalefmldes a been Proposed as gelatm corresponding proportion were taken. Each of these hardeners as for 1113mm? 111 Patent 2,992,109 of emulsion samples was coated out onto cellulose acetate C. F. H. Allen and Belgian Patent 579,914 of G evaert fil Support at a coverage f 432 f Silver and 930 Photo-Products. It has been noted that incorporation of mg of gelatin er square foot. A sample of each film heXamethylene bisfnilleimide gelatin flompositifm coating was exposed on an Eastman 1B sensitometer, roduces only a slight increase, if at all, in the melting rocessed for 5 minutes in Kodak DK-SO developer, points of the gelatin layers obtained therefrom. fixed, washed and dried with the following results:

Cone, Rel. Percent Ret. M. Compound Name g./10O Speed 7 Fog Swell F? F.

g. of gel 1 Control N,N-Hexamethylene-bis 100 1 32 0 14 716 84 88 mgt imideu 23 1.37 0.12 477 82 91 2 N,N-Hexamethylenebis- 1 46 0 l 469 77 92 isomaleimide 0.6 74 1.33 0.11 433 94 123 Do 1.2 54 1.30 0.10 329 None 212 1 Vertical swell 2 Reticulation, 3 Melting Point, F.

ll 0 monanN o-mr where n is an integer of 4 to 10.

We have found that these compounds of our invention when incorporated in gelatin layers at a concentration as little as 0.5% of the gelatin will effectively harden the gelatin so as to increase the melting point and resistance to swelling by Water of layers prepared therefrom. We have found that these hardeners have no detrimental eifect on the photographic properties of products in whose preparation they are used.

The following examples illustrate the use of compounds in accordance with the invention for gelatin hardening comparing same with the eifectiveness of bismaleimide hardeners.

in? water without processing.

perature at this point designated the melting point of the gelatin containing layer.

Example 2 A slurry of 51.2 grams of N,N-tetramethylene-bismaleamic acid in 500 ml. of dichloromethane was stirred vigorously while a solution of 82.5 grams of commercial dicyclohexylcarbodiimide in ml. of dichloromethane Was added dropwise over a period of 50 minutes. The mixture was stirred for 24 hours, then cooled and the solids were removed by filtration. The crude residue was extracted with hot benzene, filtered and evaporated to dryness. The residue was slurried with cold ether and filtered. The crude, colorless crystalline solid was recrystallized With benzene-ether to give N,N'-tetramethylenebisisomaleimide having a melting point of 146.5 to 148.5 C.

The tetramethylene bisisomaleimide prepared in Example 2 was added to separate portions of high-speed silver bromoiodide emulsion which had been panchromatically sensitized with a cyanine dye, in the proportions indicated in the table. A sample of the emulsion without hardener was also taken. Each emulsion sample was coated onto a cellulose acetate film support at a coverage of 459 mg. of silver and 1040 mg. of gelatin per square foot. A sample of each film coating was exposed on an Eastman 1B sensitometer, processed for five mine; utes in Kodak DK-SO developer, fixed, Washed and dried with the following results:

2. A composition comprising gelatin containing therein hexamethylene bisisomaleimide.

Cone., Rel. Bet, M.PI, Compound Name gJlOll Speed 1 Fog Swell 1 F. F.

g. of gel Control- 100 l. 02 17 730 74 85 N,N'-Tetramethylenebisiso- I maleimide 3 76 l. 22 12 320 None 212 D0 6 59 1. l7 10 280 None 212 1 Taken after developing, fixing and washing.

HC-O o n being an integer of 4 to 10.

3. A composition comprising gelatin containing therein tetrarnethylene bisisomaleimide. V

4. A gelatin-silver halide photographic emulsion containing hexamethylene bisisomaleimide.

5. A gelatin-silver halide photographic emulsion containing therein tetramethylene bisisomaleimide.

References Cited by the Examiner UNITED STATES PATENTS 2,726,162 12/1955 Allen et al. 106125 2,899,327 8/ 1959 Christopher et al. 106125 2,992,109 7/1961 Allen 96sl11 2,994,611 8/1961 Heyna et al. 96-111 OTHER REFERENCES Chemical Abstracts, v01. 55 (1961), pp. 19782 to NORMAN G. TORCHIN, Primary Examiner. 

1. A GELATIN-SILVER HALIDE PHOTOGRAPHIC EMULSION CONTAINING THEREIN A HARDENING AMOUNT OF 